1. Field of the Disclosure
The present disclosure relates to electronic devices and systems including and methods of using the same, and more particularly to electronic devices that includes signal clamping control modules to clamp voltages of power transistors, and systems including and method of using the same.
2. Description of the Related Art
Internal combustion engines typically include an ignition system, such as a conventional ignition system 10 in FIG. 1. The circuit for the ignition system can include a battery 12 that is coupled to a primary winding 142 of a transformer 14, such as an ignition coil, the primary winding is coupled to a collector of an insulated gate bipolar transistor 16. A control signal can be provided to the gate of the insulated gate bipolar transistor 16 to affect current flow between the collector and emitter of the insulated gate bipolar transistor 16. The control signal may be provided from an integrated circuit or another part of a vehicle having the internal combustion engine. The emitter of the insulated gate bipolar transistor 16 and the battery are coupled together and to a ground terminal. A secondary winding 144 of the transformer 14 has one terminal coupled to ground or a terminal of a battery and another terminal that produces a higher voltage signal that may be coupled to a spark plug or other ignition element.
The collector of the insulated gate bipolar transistor 16 can reach very high voltages during operation of the ignition system 10. For example, the collector may reach up to 400 volts or potentially higher during normal operation of the ignition system 10. The insulated gate bipolar transistor 16 is designed with an internal self-protection voltage clamp that is activated when the voltage difference between the collector and emitter exceeds 400 volts. At this point, the current flows between the collector and emitter of the insulated gate bipolar transistor, and the energy in the transformer is dissipated.
Because the insulated gate bipolar transistor 16 is designed to allow up to 400 volts between the collector and emitter and has an internal high-voltage clamping mechanism therein, the design of the insulated gate bipolar transistor 16 is relatively complicated. Thus, the insulated gate bipolar transistor 16 can be relatively costly. The voltage rating and the corresponding energy rating of the insulated gate bipolar transistor 16 is a significant factor in the cost of the insulated gate bipolar transistor 16.
Skilled artisans appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the invention.